When to Plant Calendula in Johnson County, WY
Johnson County, Wyoming gardeners: here's your June plan
We've pulled the most time-sensitive tasks for Johnson County, Wyoming this June and put them front and centre. Tackle them in order.
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Start calendula under lights
Give them 6–8 weeks indoors before the last frost and you'll transplant into warm soil with seedlings that are already leaping.
Before July arrives, get these ready
- First harvests: calendula
Calendula (Calendula officinalis) is a cheerful, edible-flowered cool-season annual valued by herbalists, chefs, and gardeners alike. Its golden-orange petals are used in salves, teas, and as a saffron substitute. Hardy enough to tolerate light frosts, it blooms prolifically in spring and fall, taking a pause during the hottest weeks of summer.
Johnson County, Wyoming is in USDA Zone 5a. The average last spring frost is May 17 and the first fall frost is September 21, giving you a growing season of approximately 127 days.
At an elevation of 8,281 feet, Johnson County receives approximately 23.7 inches of rainfall annually with predominantly loam soil. Summer highs average 81°F, so choose short-season varieties of Calendula to ensure they mature before fall.
Johnson County Soil Profile
Soil Type
Loam
Soil pH
6.8-7.8
Drainage
Well Drained
Calendula Planting Risk Windows
Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.
Soil Compatibility in Johnson County
How your county's soil matches Calendula's growing requirements.
Soil pH
Your soil pH (6.8–7.8) is more alkaline than Calendula prefers (5.5–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Johnson County is excellent for Calendula — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Calendula.
Organic Matter
Organic matter is moderate (2.2%). Annual compost additions will help Calendula.
How to Plant Calendula
Succession Planting Calendula
Sow every 5.7 weeks. Last sowing by Jul 13 to harvest before frost.
Calendula Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Calendula
Calendula needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.
| Month | Calendula Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.8" | 0" | ❄️ Dormant |
| Feb | — | 1.5" | 0" | ❄️ Dormant |
| Mar | — | 1.9" | 0" | ❄️ Dormant |
| Apr | — | 2.1" | 0" | ❄️ Dormant |
| May | 2.2" | 2.8" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 1.6" | 0.6" | 💧 Light watering |
| Jul | 2.2" | 2.3" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 2.5" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 2.1" | 0.1" | 💧 Light watering |
| Oct | — | 2.1" | 0" | ❄️ Dormant |
| Nov | — | 1.5" | 0" | ❄️ Dormant |
| Dec | — | 1.5" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Johnson County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Calendula Heat Requirements (GDD)
What are Growing Degree Days (GDD)?
Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.
Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.
Calendula Planting Timeline — Johnson County, WY
Calendula Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 5 | Apr 5 – Apr 19 |
| Transplant Outdoors | May 17 | May 17 – May 31 |
| Direct Sow | April 26 | Apr 26 – May 17 |
| Bloom | July 5 | Jul 5 – Sep 27 |
Plant 0.3" deep · 9" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Natural rainfall sufficient
📅 Days to Maturity
50–70 days
🧪 Soil pH
Needs 5.5–7 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 5a
📆 Growing Season
127 days in Johnson County
Growing Tips for Calendula in Johnson County
Direct sow Calendula outdoors after May 17 in Johnson County when soil has warmed and frost danger has passed.
Common pests for Calendula in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.
Johnson County receives only 24" of rain annually. Calendula needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
General growing tips
Direct-sow in early spring as soon as soil can be worked — seeds germinate in cool soil (50-65°F). In zones 7+, also sow in fall for winter/spring bloom. Deadhead consistently to extend bloom. Plants self-seed readily; save a few spent heads and allow them to drop. Harvest petals when flowers are fully open for best flavor and medicinal value.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Calendula in Other Locations
Frequently Asked Questions
When should I plant Calendula in Johnson County, WY?
Johnson County is in Zone 5a with an average last frost of May 17. Plan your Calendula planting based on this frost date — see the calendar above for exact timing.
What planting zone is Johnson County, WY?
Johnson County, Wyoming is in USDA Hardiness Zone 5a. The average last spring frost is May 17 and first fall frost is September 21.
Your Johnson County Garden Planner — Free
A 22-page printable planner built for Johnson County (Zone 5a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.